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Parallel propagating modes and anomalous spatial damping in the ultra-relativistic electron plasma with arbitrary degeneracy

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Chinese Physics B 2017年第11期26卷 76-82页

作者： H Farooq M Sarfraz z Iqbal G Abbas H A shah Department of Physics Government College University Government College University

The dispersion relations of parallel propagating modes（Langmuir mode, right and left handed circular polarized waves） in the weak magnetic field limit ｜ω-k·v｜〉〉？ are considered for ultra-relativistic arbitrary degenerate electron plasma. The results are presented in terms of moments of Fermi-Dirac distribution. The increase in the electron equilibrium number density from negative large（weakly degenerate） to positive large（highly degenerate） values of μ/Te is observed（where μ is the electron chemical potential and Te is the electron thermal energy）. As a result, shifting of the cutoff points in all the real dispersion branches towards the higher values and increasing in the band gap between unmagnetized longitudinal and transverse modes in k-space are examined. Also, the suppression of the weak magnetic field effects in weakly magnetized right handed and left handed circular polarized waves and a decrease in the longitudinal and transverse screening effects are observed in the graphical patterns due to an increase in the equilibrium number density.

关键词： degenerate Fermi gases relativistic plasmas electromagnetic waves

Unsupervised neural network model optimized with evolutionary computations for solving variants of nonlinear MHD Jeffery-Hamel problem

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Applied Mathematics and Mechanics(English Edition) 2015年第12期36卷 1611-1638页

作者： M.A.z.RAJA R.SAMAR T.HAROON S.M.shah Department of Electrical Engineering COMSATS Institute of Information Technology Department of Electrical Engineering Mohammad Ali Jinnah University Department of Mathematics COMSATS Institute of Information Technology

A heuristic technique is developed for a nonlinear magnetohydrodynamics （MHD） Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work （ANN） optimized with the genetic algorithm （GA） and the sequential quadratic programming （SQP） method. The twodimensional （2D） MHD Jeffery-Hamel problem is transformed into a higher order boundary value problem （BVP） of ordinary differential equations （ODEs）. The mathematical model of the transformed BVP is formulated with the ANN in an unsupervised manner. The training of the weights of the ANN is carried out with the evolutionary calculation based on the GA hybridized with the SQP method for the rapid local convergence. The proposed scheme is evaluated on the variants of the Jeffery-Hamel flow by varying the Reynold number, the Hartmann number, and the an- gles of the walls. A large number of simulations are performed with an extensive analysis to validate the accuracy, convergence, and effectiveness of the scheme. The comparison of the standard numerical solution and the analytic solution establishes the correctness of the proposed designed methodologies.

关键词： Jeffery-Hamel problem neural network genetic algorithm (GA) nonlinear ordinary differential equation (ODE) hybrid technique sequential quadratic programming

Maternal salinity improves yield, size and stress tolerance of Suaeda fruticosa seeds

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Journal of Arid Land 2020年第2期12卷 283-293页

作者： sye. z shah Aysha RASHEED Bilquees GUL Muhammad A KHAN Brent LNIELSEN Abdul HAMEED Institute of Sustainable Halophyte Utilization University of KarachiKarachi 75270Pakistan Govt.Degree Boys College Sector 4ENew SaeedabadBaldia TownKarachi 75760Pakistan Department of Microbiology&Molecular Biology Brigham Young UniversityProvoUT 84602USA

Shrubby seablite or lani(Suaeda fruticosa Forssk)is a perennial euhalophyte with succulent leaves,which could be planted on arid-saline lands for restoration and cultivated as a non-conventional edible or cash *** about the impacts of maternal saline environment on seed attributes of this important euhalophyte is *** study investigated the effects of maternal salinity on yield,size and stress tolerance of *** *** of *** were grown in a green net house under increasing maternal salinity levels(0,300,600 and 900 mM NaCl)until seed *** yield,size,stress tolerance and germination of the descended seeds under different maternal saline conditions were *** grown under saline conditions(300,600 and 900 mM NaCl)produce a substantially higher quantity of seeds than plants grown under non-saline condition(0 mM NaCl).Low maternal salinity(300 mM NaCl)improves seed *** produced under all maternal salinity levels display a higher tolerance to low temperature(night/day thermoperiod of 10℃/20℃),whereas seeds produced under 300 mM NaCl maternal saline condition show a better tolerance to high temperature(night/day thermoperiod of 25℃/35℃)during *** from all maternal saline conditions germinate better in the 12 h photoperiod(12 h light/12 h dark)than in the dark(24 h dark);however,seeds produced from low and moderate maternal saline conditions(300 and 600 mM NaCl)show a higher germination in the dark than those from control and high maternal saline conditions(0 and 900 mM NaCl).In general,maternal salinity is found to improve yield,size and stress tolerance of *** seeds.

关键词： euhalophyte maternal salinity salt tolerance seed germination non-saline condition Suaeda fruticosa

Optimization of aerodynamic efficiency for twist morphing MAV wing

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Chinese Journal of Aeronautics 2014年第3期27卷 475-487页

作者： N.I.Ismail A.H.zulkifli M.z.Abdullah M.Hisyam Basri Norazharuddin shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA Shah Alam 40450 Malaysia School of Mechanical Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300 Malaysia School of Materials and Mineral Resources Engineering Universiti Sains Malaysia Engineering Campus Nibong Tebal 14300Malaysia

Twist morphing （TM） is a practical control technique in micro air vehicle （MAV） flight. However, TM wing has a lower aerodynamic efficiency （CL/CD） compared to membrane and rigid wing. This is due to massive drag penalty created on TM wing, which had overwhelmed the succes- sive increase in its lift generation. Therefore, further CL/CDmax optimization on TM wing is needed to obtain the optimal condition for the morphing wing configuration. In this paper, two-way fluid- structure interaction （FSI） simulation and wind tunnel testing method are used to solve and study the basic wing aerodynamic performance over （non-optimal） TM, membrane and rigid wings. Then, a multifidelity data metamodel based design optimization （MBDO） process is adopted based on the Ansys-DesignXplorer frameworks. In the adaptive MBDO process, Kriging metamodel is used to construct the final multifidelity CL/CD responses by utilizing 23 multi-fidelity sample points from the FSI simulation and experimental data. The optimization results show that the optimal TM wing configuration is able to produce better CL/CDmax magnitude by at least 2% than the non-optimal TM wings. The flow structure formation reveals that low TV strength on the optimal TM wing induces low CD generation which in turn improves its overall CL/CDmax performance.

关键词： Aerodynamics Fluid structure interaction Micro air vehicle Optimization Twist morphing

Computational aerodynamic analysis on perimeter reinforced(PR)-compliant wing

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Chinese Journal of Aeronautics 2013年第5期26卷 1093-1105页

作者： N.I.Ismail A.H.zulkifli M.z.Abdullah M.Hisyam Basri Norazharuddin shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia School of Mechanical Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia

Abstract Implementing the morphing technique on a micro air vehicle （MAV） wing is a very chal- lenging task, due to the MAWs wing size limitation and the complex morphing mechanism. As a result, understanding aerodynamic characteristics and flow configurations, subject to wing structure deformation of a morphing wing MAV has remained obstructed. Thus, this paper presents the investigation of structural deformation, aerodynamics performance and flow formation on a pro- posed twist morphing MAV wing design named perimeter reinforced （PR）-compliant wing. The numerical simulation of two-way fluid structure interaction （FSI） investigation consist of a quasi- static aeroelastic structural analysis coupled with 3D incompressible Reynolds-averaged Navier- Stokes and shear-stress-transport （RANS-SST） solver utilized throughout this study. Verification of numerical method on a rigid rectangular wing achieves a good correlation with available exper- imental results. A comparative aeroelastic study between PR-compliant to PR and rigid wing per- formance is organized to elucidate the morphing wing performances. Structural deformation results show that PR-compliant wing is able to alter the wing＇s geometric twist characteristic, which has directly influenced both the overall aerodynamic performance and flow structure behavior. Despite the superior lift performance result, PR-compliant wing also suffers from massive drag penalty, which has consequently affected the wing efficiency in general. Based on vortices investigation, the results reveal the connection between these aerodynamic performances with vortices formation on PR-comoliant wing.

关键词： Aerodynamics Aeroelasticity Fluid structure interaction Micro air vehicle (MAV) Morphing wing

Electrical features of radio-frequency atmospheric pressure helium discharge with and without dielectric electrodes

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Plasma Science and Technology 2019年第2期21卷 60-67页

作者： H ASHRAF S z A shah H I A QAzI M A KHAN S HUSSAIN M A BADAR S NIAz M SHAFIQ Department of Physics University of Sargodha Department of Physics Quaid-i-Azam University

A comparative study of radio-frequency atmospheric pressure glow discharge(rf APGD)generated in helium with and without dielectric electrodes to investigate the effect of electrodes insulation on electrical features of APGD is presented. In the α mode, both the rf APGDs remain volumetric, stable and uniform. In the γ mode, the APGD without dielectric electrodes shrinks into a constricted plasma column whereas APGD with dielectric electrodes remains stable and retains the same volume without plasma constriction even at higher densities of discharge current. A comparison of electrical features of both rf APGDs in normal and abnormal glow discharge regimes is presented. In both APGDs with and without dielectric electrodes,impedance measurements have been performed and compared with equivalent circuit *** measured impedance data is found to be in good agreement with simulated data.

关键词： radiofrequency atmospheric pressure glow discharge dielectric electrodes plasma stability control

Renewable energy resources, policies and gaps in BRICS countries and the global impact

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Frontiers in Energy 2019年第3期13卷 506-521页

作者： Lakshmi PATHAK Kavita shah Institute of Environment and Sustainable Development Banaras Hindu UniversityVaranasi 221005India

This paper presents comparative yet extensive analysis of existing non-conventional renewable resources, energy policies and gaps in BRICS countries. An intelligent transformation to green economy to maintain natural resources is noted. Brazil has stable energy policies and is the leading producer of biofuels following hydropower until 2014 but supported wind and solar power development by tendering specific tariffs for energy generation from solar and wind. Russia needs improvement in its legal and regulatory framework with more incentives in energy policies. China is improving upon wind and hydropower but it needs strong policy measures to put cap on increased CO2 emissions. India needs revision in energy policy and requires extra incentives and consumer specific energy policies for research-infrastructure and energy generation technologies. South Africa requires lessons to increase renewable energy and reduce coal mining. Moreover, BRICS countries need to redefine their energy policies based upon their existing geographical, economical, societal and environmental conditions which will help in shaping global energy policies and more financial stability. This paper recognizes the potential of BRICS to reshape the global system paralleled with minimizing CO2 emissions. The concerted role of BRICS needs to be recognized as the leading contributor of global renewable capacity where the developed world is geared and busy to address the environmental issues.

关键词： BRICS CO2 emissions energy policies renewable

Crime forecasting:a machine learning and computer vision approach to crime prediction and prevention

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Visual Computing for Industry,Biomedicine,and Art 2021年第1期4卷 76-89页

作者： Neil shah Nandish Bhagat Manan shah Department of Computer Engineering Sal Institute of Technology and Engineering ResearchAhmedabadGujarat 380060India Department of Chemical Engineering School of TechnologyPandit Deendayal Energy UniversityGandhinagarGujarat 382426India

A crime is a deliberate act that can cause physical or psychological harm,as well as property damage or loss,and can lead to punishment by a state or other authority according to the severity of the *** number and forms of criminal activities are increasing at an alarming rate,forcing agencies to develop efficient methods to take preventive *** the current scenario of rapidly increasing crime,traditional crime-solving techniques are unable to deliver results,being slow paced and less ***,if we can come up with ways to predict crime,in detail,before it occurs,or come up with a“machine”that can assist police officers,it would lift the burden of police and help in preventing *** achieve this,we suggest including machine learning(ML)and computer vision algorithms and *** this paper,we describe the results of certain cases where such approaches were used,and which motivated us to pursue further research in this *** main reason for the change in crime detection and prevention lies in the before and after statistical observations of the authorities using such *** sole purpose of this study is to determine how a combination of ML and computer vision can be used by law agencies or authorities to detect,prevent,and solve crimes at a much more accurate and faster *** summary,ML and computer vision techniques can bring about an evolution in law agencies.

关键词： Machine learning Computer vision Crime forecasting

Residual Effect of Biochar on Soil Properties and Yield of Maize (<i>zea mays L.</i>) under Different Cropping Systems

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Open Journal of Soil Science 2018年第1期8卷 16-35页

作者： Sara, z. shah T. shah Department of Soil and Environmental Sciences Faculty of Crop Production Sciences the University of Agriculture Peshawar Pakistan

A field experiment was conducted to examine the residual influence of biochar applied previously to an established experiment at the Agriculture University Research Farm, Peshawar on soil properties and yield of maize crop during summer 2016. The experiment was established in RCB design with split plot arrangements having cropping systems (CS) in main plots and biochar (BC) in sub-plots. Cropping systems were: 1) wheat-mung bean;2) wheat-maize;3) chickpea-maize;and 4) chickpea-mung bean. During the past three seasons, each cropping system received biochar at 0, 40, 60 and 80 t·haǃ along with recommended dose of NPK in each season. For this study, maize was planted after chickpea and wheat in summer 2016. The results showed that grain yield, cobs weight and total N uptake of maize was significantly greater for chickpea-maize than for wheat-maize cropping system. Soil organic C was also significantly higher in soil under chickpea-maize than under wheat-maize cropping system. However, other yield components such as stover yield, harvest index and N concentration in grain and stover of maize and soil properties such as pH, EC and mineral N were non-significantly affected by cropping systems. With respect to residual effect of biochar grain yield of maize and bulk density of soil were maximum for treatment receiving biochar at 40 t·haǃ whereas cobs weight soil pH and mineral N were highest receiving biochar at 60 t·haǃ. Moreover, N concentration in stover, N uptake and soil organic C were maximum for treatment receiving biochar at 80 t·haǃ. However, stover yield, harvest index, N concentration in grain, and soil EC were non-significantly affected by biochar treatments. However interactions between CS × BC were significant for yield and yield parameters of maize and for soil properties (bulk density mineral N), while non-significant for harvest index, soil organic C, pH and EC. It was concluded that chickpea-maize cropping system performed

关键词： Biochar Residual Effect Soil Properties Cropping Systems Yield and Yield Components of Maize